1. Field of the Invention
This invention relates to grinding cannulas, and more particularly to apparatus for aligning and holding cannulas while they are ground.
2. Description of the Prior Art
As described in U.S. Pat. No. 3,975,864, cannulas are formed by grinding the ends of small tubes to provide a primary bevel or lance point, and two secondary bevels or lancets on both sides of the lance point. The lancets are formed by rotating the tubes to allow the lancet cuts to be made.
Since a large number of tubes are ground simultaneously, the individual tubes must be properly aligned in the apparatus. Presently, a multiplicity of the tubes are aligned prior to being mounted in a fixture on the grinding apparatus. The aligned tubes are secured on a strip of tape which serve to hold the tubes in the selected orientation while they are being mounted onto the grinding fixture. After grinding, the tubes are removed from the fixture still on the tape. The tubes are separated from the tape and placed in containers for storage or shipment.
The use of tape in aligning and mounting the tubes in a fixture on the grinding apparatus is time-consuming and wasteful. After one set of tubes is ground, the strip of tape holding them cannot be re-used. Furthermore, a number of tubes might become dislodged and disoriented before they could be secured in the grinding apparatus, resulting in improperly ground tubes or expenditure of time in realignment.
The present invention provides a cartridge to be used in conjunction with a grinding apparatus that can be loaded with tubes and hold them in the proper orientation prior to mounting on the grinding apparatus. The cartridge also is arranged to permit the tubes to rotate so that lancet cuts may be made.